PROJECT SUMMARY/ABSTRACT Background. Over half of Veterans report musculoskeletal (MSK) pain, often with mental health comorbidities. Complementary and integrative health (CIH) therapies are important non-pharmacologic treatment options for these conditions. However, CIH is not widely available at the VA. Also, practitioner-delivered therapies (i.e., acupuncture or chiropractic) are promising, but providers would like patients to be more active in their pain management by using self-care (i.e., meditation, tai chi, yoga) instead of relying on practitioner-delivered care. A critical question for the field is whether adding self-care CIH to practitioner-delivered CIH is a more effective approach than either strategy alone. However, we are unaware of anyone examining this. Also, to-date, studying CIH in large VA samples has been difficult because few facilities capture CIH use with codes in their electronic health records, and very few use the VA's standardized codes, preventing multi-site studies. In 2016, Congress passed the Comprehensive Addiction and Recovery Act mandating expansion of CIH therapies in VA. In response, 18 VA regional networks committed $5 million/yr to implement CIH therapies at 18 sites beginning in 2018, focusing on five evidence-based therapies: acupuncture, chiropractic, Tai Chi, mindfulness, and yoga. The VA's Office of Patient Centered Care and Cultural Transformation (OPCC&CT) will oversee this effort, including the data collection efforts targeting 1,000 CIH users from each of the 18 sites. We propose addressing the above gaps by continue our longstanding collaboration with OPCC&CT to capitalize on 1) the 2018 rollout of CIH in 18 VA sites and 2) our two current national/multisite studies of the effects of CIH, one on MSK pain and the other which integrates CIH patient reported outcomes (PROs) measurement into clinical care. We propose a large-scale pragmatic comparative effectiveness clinical trial to assess CIH. In the UG3 Planning Phase, as the 18 sites begin implementing CIH, we will develop and implement data collection instruments and processes that we are currently piloting to capture CIH use and PROs: 1) pain and its intensity and interference, 2) global physical and mental health and 3) fatigue. We also will examine opioid use. To inform that measurement, we will use multiple strategies, including an Advisory Board. In the UH3 Implementation Phase, we will conduct a 3-arm pragmatic trial using an encouragement design to assess the longitudinal comparative effectiveness of: 1) practitioner-delivered care (acupuncture or chiropractic care) combined with self-care (Tai Chi, meditation/mindfulness or yoga) compared to 2) practitioner-delivered care alone or 3) self-care alone. We will examine outcomes at 3 and 6 months for OPCC&CT's target sample of 18,000 CIH users. We will use randomized ?nudges? (e.g., educational brochures with class listings) tailored to each site to encourage Veterans who use one type of CIH to consider a combination of therapies.